Connection for endless chain mechanism



Oct. 25, 193-8. F. M. BLANCHARD CONNECTION FOR ENDLESS CHAIN MECHANISM 2 Sheets-Sheet 1 Filed May 15, 1957 O 25, 1938. F. M. BLAN'CHARD 2,1 4,222

CONNECTION FOR ENDLESS CHAIN MECHANISM Filed May 15, 1937 2 Sheets-Sheet 2 ATTORNEY Patented Oct. 25, 1938 UNITED STATES.

, V 2,134,225; s v I CONNECTIONFOR ENDLESS CHAIN-MECHQ.

Floyd Martin Blanchard, London, Engl pplication May 15, 1937, Serial No. 142,901 7 In Great Britain October 13, 1936 I This invention relates to bucket dredges and also to similar endless chain mechanisms, such as bucket or 'step or link' conveyors, caterpillar For convenience, in; the following description and claims, reference tractor bands and the like.

will be made to dredge bucket chains, but it is to be understood that this term is intended to include other endless chain mechanisms, 'and that the term dredge bucket, which will also be employed, is intended to cover also the equivalent elements of said similar mechanisms.

The front eyes of a dredge bucket are subject during service to wear and elongation. Wear is caused by a pin, not provided with a locking device, moving loosely about in the bucket eye.

This wear is not confined to the bucket eye with consequent enlargement, but also causes a reduction inthe diameter of the pin on one side only, towards the front of the bucket. This reduction in area causes a proportionate reduction of strength, and present-day practice is to make bucket pins of excessive diameter tooffset this.

Manufacturing methods demand large tolerancesin machining the bucket eyes as well as in turning the diameter of the bucket pins. This is done in order to ensure an easy fit in assembly of pin and bucket. Consequently the bearing of the' front eye of the bucket on the pin is neveras it should be, even'when new. During service, the

front eyes of buckets tend to' become elongated on the axis parallel to the base of the bucket. This elongation is caused by application of excessive overloads to the bucket band in order to overcome difficult and unavoidable digging conditions,

i. The accumulation of wear and elongation causes an excessive amount of clearance between pin and bucket eye, which in turn permits undesired movement and consequent increased wear.

It is known to "provide, in one of the forward eye stocks of each'bucket, a recess which is adapted to accommodate an L-head integral with the bucket pin, both the recess'and the L-he'ad having parallel lateral surfaces. When the pin is first inserted this head is a driving fit in'the L recess, but under the twisting forces exerted by friction on the pin during the turning of the bucket about the tumblers, the head very soon slackens and allows both lateral and-axial movement of the pin in the forward bucket eyes; This continued movement eventually results in excessive wear of both pin and bucket eye which is disadvantageous, because normally no provision is made for dealing with such wear, as by the provision of renewable bushes, in the forward eyesf 13'Claims. (crew-.191)" I L It has therefore been recognized that some means-'isdesirable for locking the pin head to prevent both lateral and 'turningmovement of the pin relative tothe "forward eyes in which it and also inthefbucket eye 7v According to one means previously proposed .is locatedin order" to eliminatewear on t'he pin for achievingthis purposathe L-head o'fa'bucket' pinis provided with a tapering form and coacts with tapering walls-oFa recess in' the bucketso that when onceset up theco-o'peration "of the surfaces holds the pin rigid-and also takes up pressure arisingfrom' the pull of the adjacent bucket.

ing parallel sides, becaus'' the tension in the bucket generally is spasmodic and repeated reversals tend to urge the pin backwards to the rear par-t 0f the forward eye, slackeningthe taper and a lateral surface of the recess, this block being' likewise tapered, but in the opposite direction to the head, to enable it to bedrawn" or driven-so as to lock the pin head between" said block and the opposite lateral surface of the recess and thereby prevent turning movement of-the pin in the for-' ward eye. However, even this additional means is subject, though to a lesser extent, to the dis advantage that the spasmodic reversals of tension in the bucket chain may drive the tapering'head out of co-operation with-the locking block and eventually cause the slackness which leads to movement and wear between thepin and the forward eye stocks. i s

which'head is located in a recess in one of the forwardeye stocksof the bucket; against 'move' ment with respect to said' forward eye. The'ime proved means comprises the combination with the bucket pin of a" locking wedge adapted to engage between'theend surface of said head and the end surfaceof the recess, for the purpose of urging the pin into firm'contact with the forward part of the bucket eye, and a lateral surface of the head'into engagement with the lateral surface of the recess against which ittends to bear under the twisting forceapplied to the pin when the bucket and that preceding it pass round one In practicefsucl'i a head'sufiers to some extent the same disadyantages as ahead hav" v 140 The present invention provides improved means for positively lockingthe L-hea'd of a bucket pin,

of the tumblers, whereby the pin is embraced by abutments serving to withstand spasmodic reversals of tension in the bucket chain and also twisting forces exerted frictionally on the pin in both directions.

Preferably, the wedge is associated with screw means enabling the application of strong force to draw it between the end surfaces of the pin head and the recess. 3

The invention further includes the combination, in a dredge, of a pin having an L-head, a

locking wedge, and a recess in one of the forward eye stocks of a bucket,-the recess housing the pin head and the wedge, with the wedge en gaging between the end surface of the head and the end surface of the recess, for the purpose above set forth. 7

In the application of screw means to the wedge in the combination last mentioned, the wedge may have a threaded shank located in aslot'ted abutment adjacent the recess, with a nut engaging said shank and bearing on the abutment. Alternatively, the wedgemay be internally drilled or tapped to receive a drawbolt or stud mounted in an apertured abutment adjacent therecess. If desired, the co-operating surfaces of the wedge, the recess and the head, or alternatively a lateral surface of the head and the co-operating lateral surface of the recess, may be inclined, or provided with steps, or tongues-andgrooves, for preventing axial movement of the pin when assembled.

- Three embodiments of the invention will be described, by way of example, with reference to the accompanying drawings, wherein:-

Fig. 1 .is a. side view of the base of a dredge bucket provided with one form of locking means according to the invention;

Fig. 2 is a fragmentary half-section on the line lI-IIII of Fig. 1.;

Fig. 3 is a view of a variation, corresponding to the left-hand part of Fig. 1; 1

Fig. 4 is a similar view of another variation, and

Fig. -5 is a section on the line V--V. of Fig. 4.

The base of the bucket I is provided, as shown in Figs. 1 "and 2, with a pair 'of forward eye stocks 2, which are spaced apart to allow the insertion between them of the rear eye stock 3 on a preceding bucket Ia. Thertwo buckets are connected together by a pin -4 having an L- head 5 housed in a recess 6 in one of the forward eye stocks 2, passing through the forward eyes I of the bucket I and the rear eye 8 :of the bucket la. The end surface 9 of the pin head is inclined to the longitudinal centre line of said head, and the recess 6 has an end surface In presented by a rib l l, which surface is substantially perpendicular to said centre line. A wedge I2 is accommodated between these end surfaces. Further, the wedge has an integral threaded shank I3, and a slot I4 is provided in arib l5, constituting the upper wall of the recess, to enable the location of the wedge in the end of the recess prior to the insertion of the pin head. When the latter has been inserted, a nut l6, engaging the shank l3 and bearing on the upper surface of the rib I5, is turned to draw the wedge 12 upwards between the surfaces 9 and I0. Thereby, the end of the pin 4 is firmly pressed against the forward part of the "eye 1, and the upper lateral surface I! of the head 5 is caused firmly to abut the lower surface of the rib IS. The pin head is thus locked positively and rigidly against all the forces to which it is subjected both laterally and longitudinally of the head, and movement of the pin in the forward eye stocks is thereby prevented. Wear of the forward eye 1 is accordingly avoided, such wear as occurs being confined to the rear part of the rear eye 3, where it is provided for by means of a removable anti-friction half-buch l8, as shown. spasmodic reversals of the tension in the bucket chain are met by the solid bearing of the end surface 9 of the pin head, through the wedge l2, on the rib ll. Further, the twisting forces on the pin, which are for the most part applied clockwisein the arrangement shown as the buckets pass round the tumblers, are borne by the bearing of the surface I! upon the rib i5, and reversed or anticlockwise twisting forces, which are usually of lesser magnitude and not so often applied, are borne by the wedge I2 against which the inclined end surface 9 of the head is firmly locked. It is therefore unnecessary to have the lower surface IQ of the head 5 in contact with the lower surface 20 of the recess 6 and a gap may conveniently be left as shown, enabling machining of said surfaces [9 and 20 to be eliminated.

'In this embodiment, the surfaces 9 and I0 and the co-operating surfaces of the wedge l2 may be mutually formed to afford axial locking of the ,pin, or the lateral surface I! and the cooperating surface of the rib 15 may be formed to the same end if the space between the surfaces l9 and 20 is sufficient to allow anti-clockwise displacement of the head 5 during insertion in or removal from the recess to enable such mutually locking surfaces to clear one another. The head may thus be locked with its inner surface 34 hearing on a flat boss 35 in the recess positively to prevent endwise movement of the pin. 7

In the variation shown in Fig. 3, the end surface-2| of the pin head 30 is disposed perpendicularly to the centre line, and the surface 22 of the abutment rib 23 is accordingly inclined to said centre line. Further, the wedge 24, as shown, has a tapped aperture 25 adapted to receive the threaded shank of a stud 26 which is passed through a slotted hole 21 in the rib 28 constituting the upper wall of the recess 29, such hole permitting forward movement of the stud.

In this arrangement again, when the wedge 24 is drawn upwards by rotation of the stud 26, the end of the pin 4 is firmly pressed against the forward part of the eye 1. Further, the upper lateral surface 3| of the head 30 is frictionally urged by the wedge 24 against the lower surface of the rib 28.. spasmodic reversals of the tension in the bucket chain are supported by the solid bearing of the end surface 2| of the pin head 30, through the wedge 24, on the rib 23. Major or clockwise twisting forces on the pin are supported by the abutment of the surface 3| ofthe latter against the rib 28.

In this arrangement, endwise locking of the pin against the boss 35 may be ensured by suitable forming of the surfaces 2| and 22 and the co-operating surfaces of the wedge 24 .Figs. 4 and 5 show in elevation and in section a-nother'varia'tion, wherein the head 36 of a pin 4 is reduced in size, with consequent reduction of weight and cost of material. The arrangement includes a wedge block 31 located between the end surface 38 of the pin head 36 and an abutment surface 39 of a rib -40 of the bucket structure, which surfaces are both inclined, in Opposite directions, to the longitudinal axis of the head. Further, both the surfaces 38 and are also inclined in plan, and the coacting's'ur faces of the wedge block 3! are correspondingly inclined, so that the block is substantially rhomwards through ahole 43 in a rib 44, which hole is splayed downwards, as shown in Fig. 4, to enable the insertion of the associated bolt and wedge block when the pin head 36 is already 10% cated in the recess, and is also slotted to allow longitudinal movement of the bolt as the wedge is drawn up. A nut 45, which engages the bolt, bears on the upper surface of the rib 44 and serves by the interaction of the wedge block 3'! and surface 38 to draw theupper lateral surface 46 of the pin head 36 into engagement with the lower abutment surface 41 of the rib44, to lock the pin positively against turning movement in the eye 1. At the same time the pin is pressed forward against the front half of the eye I, to prevent movement under spasmodic variations or reversals of tension in the bucket chain, any reversals which occur being supported by the solid bearing of the pin head"36 through 'the wedge block 31, on the rib 40. Further, the inclination in plan of the surfaces 38 and 39 cause the wedge when drawn up by the bolt 4| to press both its own inner surface 48 and the inner surface 34 of the pin head 36- against a flat boss 35 in the back of the recess, to effect positive looking together of the parts and prevent endwise movement of the pin 4.

Evidently, other constructional variations may be made, as by providing the wedge block in an embodiment similar to any of those shown with an integral shank, a stud or a drawbolt according to convenience. Further, modifications may be made as required, for example, in applying the invention to other endless chain mechanisms, such as link conveyors, tractor bands and the like above referred to.

I claim:-

1; For use in a dredge bucket having a forward eye stock with a circular eye and a recess the periphery of which is constituted by upper and lower surfaces joined by one part-cylindrical end surface and one transverse plane end surface, the combination of a bucket pin locatable in said eye, an L-head on said pin adapted to lodge in said recess, a planeend surface on said head, and a locking wedge block adapted to engage between said plane end surfaces to urge said head into firm contact with said part-cylindrical surface.

2. For use in a dredge bucket having a forward eye stock with a circular eye and a recess the periphery of which is constituted by upper and lower surfaces joined by one part-cylindrical end surface coincident with the periphery of said eye and one transverse plane end surface, the combination of a bucketpin locatable in said eye, an L-head on said pin adapted to lodge in said recess, a plane end surface on said head, a locking wedge block adapted to engage between said plane end surfaces, and screw means associated with said wedge block to draw it between said plane end surfaces to urge said pin into firm contact with said part-cylindrical surface.

3. Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye in the stock, a recess in the outer surface of the stock, the periphery of said recess being constituted by upper and lower surfaces joined by one part cylindrical end surface and one transverse plane end surface, a pin extending through the-eye,,an L-head on the pin lodged in said recess, a plane end surface on said head, and a transverse locking wedge block engagingbetween said plane end surfaces to urge the'head into firm contact with said part-cylindrical surface.

4; Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye in the stock, a recessv in the outer surface of the stock, the periphery of said recess being constituted by upper and lower surfaces joinedby one part-cylindrical end surface coincident with the periphery of the eye and one transverse plane end surface, a pin extending-through the eye, an L-head on the pin lodged in said recess, a plane end surface on said head, a transverse locking .wedge engaging between said plane end surfaces, an apertured abutment on the recessed eye stock adjacent the recess, a screw-threaded shank on the wedge block passing through said apertured abut- 1 mentanda nut on the shank turnable to draw the wedge block transversely between said plane end surfaces to urgethe pin into firm contact with said part-cylindrical surface.

5. Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye in the stock, a recess in the outer surface of the stock, the periphery of said recess being constituted by upper and lower surfaces joined by one part-cylindrical end surface coincident with the periphery of the eye and one transverse plane end surface, a pin extending through the eye, an L-head on the pin lodged in said recess, a plane end surface on said head, a transverse locking wedge block engaging between said plane end surfaces, an apertured abutment on the recessed eye stock adjacent the recess, and a drawbolt extending through said abutment and engaging the wedge block for drawing it transversely between said plane end surfaces to urge the pin into firm contact with said part-cylindrical surface.

6. Connection for endless dredge bucket chain comprising the combination of 'a forward bucket eye stock, a circular eye in the stock, a recess in the outer surface ofthe stock, the periphery of said recess being constituted by upper and lower surfaces joined by one part-cylindrical end surface coincident with the periphery of the eye and'one transverse plane end surface, a pin extending through theeye, an L-head on the pin lodged in said recess, a plane end surface on said head, a transverse locking wedge block engaging between said plane end surfaces, an apertured abutment on the recessed eye stock'adjacent the recess, a screw-threaded shank on the wedge block passing through said apertured abutment and a nut on the shank turnable to draw the wedge block transversely between said plane end surfaces to urge the pin into firmcontact with said part-cylindrical surface, said apertured abutment being formed to permit insertion of the wedge-block in the recess prior to the insertion of the pin head,

'7. Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye in the stock, a recess in the outer surface of the stock, the periphery of said recess being constituted by upper and lower surfaces joined by one part-cylindrical end surface coincident with the periphery of the eye and one transverse pian-e end surface, a pin extending through the eye, an JL-head on the pin lodged in said recess, a plane end surface on said head, a .transverse locking wedge engaging between said plane end surfaces, an apertured abutment on the recessed eye stock adjacent the recess, and a drawbolt extending through said abutment and engaging the wedge block for drawing it transversely between said plane end surfaces to urge the pin into firm contact with said part-cylindrical surface, said apertured abutment being formed to permit insertion of the L-head in the recess prior to the insertion of the wedge block between the end surfaces and the drawbolt associated therewith through the apertured abutment.

8. For use in a dredge bucket having a forward eye stock with a circular eye and a recess the periphery of which is constituted by upper I and lower surfaces joined by one part-cylindrical end surface and one transverse plane end surface inclined in end elevation to the longitudinal axis of said recess, the combination of a bucket pinlocatable in said eye, an L-head on said pin adapted to lodge in said recess, a plane end surface on said head, and alocking wedge block adapted to engage with surface contacts between said plane end surfaces to urge said head into firm contact with said part-cylindrical surface.

9. For use in a dredge bucket having a forward eye stock with a circular eye and a recess the periphery of which is constituted by upper and lower surfaces joined by one'part-cylindrical end surface and one transverse plane end surface 1 normal in end elevation to the longitudinal axis of said recess, the combination of a bucket pin locatable in said eye, an L-head on said pin adapted to lodge in said recess, a plane end surface on said head inclined in end elevation to the longitudinal axis of said head, a locking wedge block adapted to engage with surface contacts between said plane end surfaces, and screw means associated with said wedge block todrawv it between said plane end surfaces to urge said head into firm contact with said part-cylindrical of said recess, a pin extending through the eye,

an L-head on the pin lodged in said recess, a plane end surface on said head normal in end elevation to the longitudinal axis of said head, and a transverse locking wedge block engaging with surface contacts between said plane end surfaces to urge the head into firm contact with said part-cylindrical surface. 1

11. Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye' in, the stock, a recess in the outer surface of the stock, the periphery of said recess being constituted by upper and lower surfaces -joined 'by one part-cylindrical end surface coincident with the'periphery of the eye and-one transverse plane end surfaceinormal in end elevation to the longitudinal axis of said recess, 'a pin extending through the eye, an L-head on the pin lodged in said recess, a plane end surface on said head inclined in end elevation to thelongitudinal axis of said head, a transverse locking wedge'engaging with'surface contacts between said plane end surfaces, an apertured abutment on the recessed eye stock adjacent the'recess, a screw-threaded shank on the wedge block passing through said apertured abutment and a nut on the shank turnable to draw the wedge block transversely between said plane end surfaces to urge the pin into firm contact with said part-cylindrical surface.

12.. For use in a dredge bucket having a forward 'eye stock with a circular eye and a recess theperiphery of which is constituted by upper and lower surfaces joined by one part-cylindrical end'surface coincident with the'periphery of said eye and one transverse plane end surface, the combination ofa bucket pin locatable in said eye, an L-head on said pin adaptedto lodge in said recess, 'aplane end surface on said head, a locking wedge block adapted to engage between said plane end surfaces, and screw means associated with said wedge block to draw it between said plane end surfaces, one effective surface of the wedge block engaging the end surface on the head with surface contact, said end surface on the head being inclined in end elevation to the longitudinal axis of the head and also inclined in plan to said axis to enable the wedge block to urge said pin into firm contact with said part-cylindrical surface and into the recess for positively preventing 'endwis'e movement of the pin, and the other effective surface of the wedge block being inclined in end elevation to said axis.

13: Connection for endless dredge bucket chain comprising the combination of a forward bucket eye stock, a circular eye in the stock, a recess in the outer surface of the-stock, the periphery of said recess being constituted by upper and lower surfacesjoined by one part-cylindrical end surface coincident with the periphery ofth'e eye and one transverse plane end surface inclined in end elevation to the longitudinal axis of said recess and also inclined in plan to said axis, a pin extending through the eye, an L-head on the pin lodged in said recess, a plane end surface on said head inclined in end elevation to the longitudinal axis of said head and also inclined in plan to said axis, a transverse locking wedge block engaging between said plane end surfaces with surface contacts, an apertured abutment'on the recessed eye stock adjacent the recess, and a drawbolt extending through said abutment and engaging the wedge block for drawing it transversely between said plane end surfaces to urge the head into firm contact with said part-cylindrical surface and into the recess for positively preventing endwise movement of the pin.

FLOYD MARTIN BLANCHARD. 

